Nozzle for production of fog or mist



Aug. 21, 1962 R. R. CURTIS NOZZLE FOR PRODUCTION OF FOG OR MIST Filed Dec. 12, 1960 IN V EN TOR.

RUSSELL R. CURTIS BY WWW,

ATTORNE S 3,050,262 Patented Aug. 21, 1962 3,050,262 NOZZLE FOR PRODUCTIGN F FOG 0R M151 Russell R. Curtis, Westfield, 11111., assignor to Curtis Automotive Devices, Inc., Westfield, 11111., a corporation of Ohio Filed Dec. 12, 1960, Ser. No. 75,203 4 Claims. (Cl. 239400) This invention relates particularly to a nozzle for producing and dispersing fogs or mists, and particularly to such a nozzle which is capable of producing a widely variable fog or mist pattern.

In the art of producing and dispersing fogs or mists there are often rather widely varying requirements for directing the fogs. Sometimes it is desired to cover a rather wide area, to blanket a relatively large space with the fog, for example, to disperse an insecticide fog. On other .occasions a well directed and concentrated fog pattern may be needed to saturate a relatively small area. Such varying requirements may exist for the same fog dispersing machine, and possibly for a single use of the machine, thus it is advantageous to obtain good atomization and a wide range of dispersion patterns in a single nozzle.

The primary object of this invention is to provide a novel atomizing nozzle, particularly for fog or mist production and dispersion, which may be controlled quick. ly and easily to produce a widely varying dispersion pattern.

Another object of the invention is to provide such a nozzle which will thoroughly atomize all liquid introduced thereto.

A further object of the invention is to provide such a nozzle which will produce a fog or mist pattern varying essentially uniformly between a nearly cylindrical column and a wide angle conical dispersion.

Other objects and advantages of the invention will be apparent from the following description, the accompanying drawings and the appended claims.

In the drawings- FIG. 1 is a longitudinal section through a nozzle constructed in accordance with the invention, and with the gas supply and controls shown schematically;

FIG. 2 is a front end view of the nozzle, also showing schematically the liquid supply;

FIG. 3 is a sectional view, on a reduced scale, taken on line 3-3 of FIG. 1, and showing the tangential entry of gas and liquid into the nozzle tube; and

FIGS. 4 and 5 are schematic views illustrating the extreme pattern conditions which may be attained by the nozzle.

Referring to the drawing, which illustrates a preferred embodiment of the present invention, the nozzle includes a main or central tube terminating at its outer or discharge end 12 in a sharp edge 13 which surrounds and defines the discharge end of the main tube. The rearward end of the tube is closed by a wall 14, and a flow of gas at relatively high velocity is directed into the main tube transversely to the longitudinal axis thereof through the supply conduit or tube 15. As best shown in FIG. 3, this tube 15 directs the high velocity gas flow essentially tangentially into the main tube 10, and the gas is swirled thereabout, discharging across the sharp edge 13, which forms a sharp-edged nozzle, as a swirling stream which will tend to expand somewhat as it passes away from the discharge end of the nozzle, by reason of the centrifugal velocity of the swirling gas.

For purposes of explanation, it will be assumed that the gas used in air under suitable pressure, which may be supplied for example by a blower indicated schematically (FIG. 1) through suitable conduits 21 and 22 which are also shown schematically in FIG. 1. It should be understood, however, that other gases high velocity may be used if desired.

Liquid to be atomized, to form a mist or fog with the air stream issuing from the nozzle, is supplied through a tube or pipe 25 which opens essentially transversely into the tube 15. An essentially non-atomized flow of liquid is directed through the pipe 25, and the aspirating eifect of the gas stream across the sharp edge nozzle 27 at the end of this pipe will be sufiicient to draw the liquid into the gas stream. The liquid may be supplied from any suitable source by any convenient means, and for purposes of illustration a supply is shown schematically in FIG. 2 as including a tank 28 connected into a constant level float valve control bowl 30, and thence through a supply line 31 to the pipe 25. Any other suitable liquid supply may be used, it being understood that it is not necessary to supply the liquid under any substantial pressure.

The liquid from tube 25 is aspirated through the air entrance tube 15 and enters the high velocity gas flow passing into the main nozzle tube 10, which the flow enters tangentially. The flow will describe an essentially helical path, as indicated by arrows 32 in FIG. 1, toward the discharge end 12. The liquid will for the most part deposit in a thin even film on the inner surface of tube 8, and the gas flow therethrough will move this film rapidly toward the discharge end 12, where the film is broken into fine particles, as it is blown from the sharp edge 13. This produces a swirling expanding fog or mist flow.

For purposes of increasing the dispersion, as to give broad dispersal immediately beyond the nozzle, as well as to assist in blowing the film of liquid from sharp edge 13, high velocity fas from the supply line 21 is admitted through a control valve 35 and supply line 36 to an inner or central nozzle tube 40 which is mounted concentrically within the main tube 10 and terminates in a dis charge end 42 which is preferably somewhat within, though adjacent, the discharge end 12 of the main tube. A deflector 45 carried on a shaft 46 is mounted beyond the end of the inner tube discharge 42, arranged to deflect or direct gas flow through the tube 40 outwardly in a divergent essentially conical pattern which passes across the sharp edge 13 of the main tube. The deflector shaft 46 is supported in a spider 47 or the like which is designed to provide a minimum of restriction to gas flow through the inner tube 40.

This gas flow may be controlled by the valve 35, and passes directly coaxially within the main tube 10, issuing as a forwardly directed and outwardly dispersing stream across the main flow of fog or mist. Thus, the gas flow from the inner tube 40 tends to cause the mist or tog flow pattern to diverge in conical fashion, giving the desired broad dispersal, and the amount of such divergence may be controlled by metering the gas flow through tube 40 by means of valve 35. The divergent eifect of this inner, and outwardly diverging, flow is shown in FIG. 4, producing the wide spray pattern indicated generally at 48. If desired, the deflector 45 may be provided with some adjustment by threading the shaft 46 into the spider 47, but it should be understood that the deflector is maintained stationary during normal use of the nozzle, with the desired variation of divergence in mist pattern being normally controlled through the valve 35.

Surrounding the main tube 10 is an outer tube 50 which has a discharge end defined by an inwardly deflector end portion 52, which is adjacent and surrounding the main nozzle discharge 12. High velocity gas is introduced into the outer tube 511 through its supply tube 53, being obtained through a supply line 54 and control valve 55 from a branch line 55 which is in turn connected to the main supply line 21.

supplied at If high velocity gas is essentially shut off from inner tube 40 and admitted through tube 53- to the outer nozzle tube 50, this gas will flow essentially coaxially out of the outer tube, being directed inwardly a slight amount by the deflecting end 52, and will provide a nearly cylindrical mist or fog pattern which can be concentrated for impingement in a small area. This concentrating effect of the outer gas flow can be varied by manipulation of the valve 55, or in some other way metering the gas flow into the outer nozzle tube 50. The concentrating effect is illustrated at essentially the minimum pattern desired, in FIG. 5, by the lines 57. It will be noted from the arrows in FIG. 5 that in this condition it is preferable that the air flow be directed only into the main tube and the outer tube 50.

Accordingly, the present invention provides for a widely variable pattern of mist or fog spray with a construction which is simple and economical to manufacture, and which can be readily and quickly controlled through manipulation of valves or like metering devices. By appropriate metering controls it is possible to obtain any pattern desired between the extremes indicated generally in FIGS. 4 and 5. Thus, the desired concentration or dispersal of the fog or mist can be quickly varied to suit the needs of a particular application, and can be changed during the course of operation.

While the form of apparatus herein described constitutes a preferred embodiment of the invention, it is to be understood that the invention is not limited to this precise method of apparatus, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is:

1. A nozzle construction for atomizing a liquid in a gas flow and producing a widely variable pattern of fog, or mist, comprising a main nozzle tube terminating in a. sharp circular edge surrounding and defining the discharge end thereof, means directing a relatively high velocity flow of gas in a swirling path about the. longitudinal axis of said tube and out said discharge end, means constructed to discharge liquid into the gas flow in said main tube for deposit as a film on the interior surface of said main tube, and for atomization thereof by the gas flow across said sharp edge, an inner gas tube mounting concentrically within said main tube and terminating adjacent said discharge end thereof, deflector means cooperating with said inner tube to direct gas flowing therefrom outwardly across the swirling mist flow from said main tube to disperse said mist flow in a generally conical pattern, and means supplying a controllable flow of gas through said inner tube to vary the dispersing effect of gas flow from said inner tube upon the mist flow issuing from said main tube.

2. A nozzle construction for atomizing a liquid in a gas flow and producing a widely variable pattern of fog or mist, comprising a-main nozzle tube terminating in a sharp circular edge surrounding and defining the discharge end thereof, means directing a relatively high velocity flow of gas in a swirling path about the longitudinal axis of said tube and out said discharge end, means constructed to discharge liquid into the gas flow in said main tube for deposit as a film on the interior surface of said main tube and for atomization thereof by the gas flow across said sharp edge, an outer gas tube surrounding said main tube and having a deflecting surface adjacent and surrounding said sharp edge directing a flow of gas in an inward direction across said discharge end of said main 4. tube to concentrate the mist flow discharging therefrom, means supplying a controllable flow of gas through said outer tube to vary the deflecting effect on said mist flow of the gas flow from said outer tube, an inner gas tube mounting concentrically within said main tube and terminating adjacent said discharge end thereof, deflector means cooperating with said inner tube todirect gas flowing therefrom outwardly across the swirling mist flowfrom said main tube to disperse said mist flow in a generally conical pattern, and means supplying a controllable flow of gas through said inner tube to vary the dispersing effect of gas flow from said inner tube upon the mist flow issuing from said main tube.

3. A nozzle construction for atomizing aliquid in a flow of air and producing a widely variable fog or mist pattern, comprising a cylindrical main nozzle tube terminating in a sharp circular edge surrounding and defining the discharge end thereof, means directing a relatively high velocity flow of air tangentially into said tube for producing a swirling flow of air therewithin discharging across said sharp edge, means connected to introduce liquid into the gas flow entering tangentially into said main tube for dispersing liquid particles deposited on the inner surface of said tube as swirling flow of mist issuing therefrom to assure thorough atomization of th liquid, means for introducing a relatively high velocity flow of air around said sharp edge of said main tube and directed coaxially of said main tube to produce a concentrating effect upon the mist flow from said main tube, and means for introducing a flow of air centrally within said mist flow and directed forwardly and outwardly of said main tube across said sharp edge to produce a dis-- persing eifect upon the mist flow tending to produce a wide angle conical dispersion of mist flow.

4. A nozzle construction for atomizing a liquid in afiow of air and producing a widely variable fog or mist pattern, comprising a cylindrical main nozzle tube ter-' minating in a sharp circular edge surrounding and defining the discharge end thereof, means directing a relatively high velocity flow of air tangentially into said tube for producing a swirling flow of air therewithin discharging across said sharp edge, means connected to introduce liquid into the gas flow entering tangentially into said main tube for dispersing liquid particles deposited on the inner surface of said tube as swirling flow of mist issuing therefrom to assure thorough atomization of the liquid, an inner tube mounted coaxially within said main nozzle tube, means directing a controlled flow of air through said inner tube in a directly axial path, and deflector means cooperating with said inner tube to disperse the flow of air therefrom outwardly across said sharp edge to produce a dispersing effect upon the mist flow tending to produce a wide angle conical dispersion of the mist flow.

References Cited in the file of this patent UNITED STATES PATENTS 1,493,584 Wills May 13, 1 924 1,567,482 Anthony Dec. 29, 1925 2,006,757 Bostrom et al. July 2, 1935 2,072,281 Simonin Mar. 2, 1937 2,532,711 Goddard Dec. 5, 1950 2,813,750 Marantz Nov. 19, 1957 2,868,587 Hegmann Jan. 13, 1959 FOREIGN PATENTS 904,557 France a---" Mar. 5, 1945" 

